Ready to feel old? It's hard to believe, but on this day 20 years ago Titanic: The Movie first premiered on cinema screens in the US.

The three-hour-long blockbuster, which set the love story of passengers Jack (Leonardo DiCaprio) and Rose (Kate Winslet) against the backdrop of the liner's tragic maiden voyage, premiered in the US on December 19, 1997.

It went on to become the top grossing film of all time, bagging some $2 billion worldwide (another James Cameron movie, Avatar, has since surpassed that).

Titanic brought the ill-fated story of the White Star liner to a whole new generation, cementing its status as the world's most famous ship and teeing up a series of global commemorations on the centenary of its sinking, in April 2012.

The cultural phenomenon has also been a boon for Belfast, birthplace of RMS Titanic and today home to the world's largest Titanic visitor experience.

The £100m Titanic Belfast opened in 2012, and has since welcomed over four million visitors, last year being named the World's Leading Visitor Attraction.

Celebrating the milestone anniversary, the visitor experience is hosting a red-carpet, movie-themed afternoon tea by its replica Grand Staircase, including a movie showing in the Titanic Suite. It starts at 7pm and costs £35pp, with a glass of Prosecco.

It has reason to celebrate. In its first three years alone, Titanic Belfast generated some £105m in additional tourism spend for the region, and hosted over 1,500 events ranging from Queen Elizabeth’s Jubilee lunch to a G8 Summit Reception.

It has also served as an anchor project for the growth of Titanic Quarter, and a catalyst for development in Belfast - set to continue apace in 2018.

"Titanic Belfast has been transformative for tourism in Northern Ireland," as Tourism NI Chairman Terence Brannigan has put it, "and has helped deliver the impressive levels of hotel growth that we are seeing today across the city."

Titanic tourism isn't confined to the showpiece itself, of course.

Belfast is also home to the original tender, SS Nomadic, and Titanic-themed experiences range from audio trails to Segway tours.

This September, a €32m Titanic Hotel opened in the former Harland & Wolff Headquarters, incorporating the drawing rooms in which the ship itself was designed.